Upate Active Directory User's Manager with Powershell

Problem,

Need to replace manager for multiple users in Active Directory (AD)

Solution
First we need to find what users have a giving manager.

This script will query AD for users with given manager SAM account name.

#

#   Get AD User's Manager

#

#

Param(

    [Parameter(Mandatory=$false,

        ValueFromPipeline=$true)]

        $FindManagerSamAccountName

    ,[Parameter(Mandatory=$false,

        ValueFromPipeline=$true)]

        $FindUserSamAccountName 

)

#Check if AD is installed

$ADUsersManagers = ""

    If (!(Get-Module ActiveDirectory)) {

        Import-Module ActiveDirectory

    }

$ADUserList =""

if ([string]::IsNullOrEmpty($FindUserSamAccountName)) {

    $ADUserList = Get-ADUser -Filter { Enabled -eq $true } -Properties Manager 

    } else {

    $ADUserList = Get-ADUser -Filter {SamAccountName -eq $FindUserSamAccountName } -Properties Manager                 

    }

$ADUsersManagers = $ADUserList|Select-Object Name,SamAccountName,@{n='ManagerSamAccountName';e={(Get-aduser $_.Manager).SamAccountName}} 

   if (![string]::IsNullOrEmpty($FindManagerSamAccountName)) {

        $ADUsersManagers |Where-Object {($_.ManagerSamAccountName -eq $FindManagerSamAccountName)}

        } else {

            $ADUsersManagers}